1. Field of the Invention
The invention relates to a floor tile, in particular a laminate panel, parquet element veneer floor element, ready-to-lay parquet element or such like, with an edge profile on at least two opposite edges in the form of a modified groove and tongue joint for the purpose of connecting adjacent tiles, with a simultaneous arrangement consisting of a set of one groove and one tongue on each of at least two edges of which the tongue on one edge of a first tile and the groove in an associated edge of a second tile rise obliquely upwards from the bottom of the tile.
2. Description of the Related Art
A floor tile of this type is disclosed in DE 33 43 604 C2. In this prior art tile, the act of connecting two identical tiles results in a xe2x80x9cmodifiedxe2x80x9d groove and tongue joint in that adjacent tiles are held in position by the joint relative to each other in both the vertical and horizontal directions, i.e. they cannot become unintentionally separated. Although this horizontal fixation can also be achieved by glueing together adjacent tiles provided with a simple groove and tongue joint, the glueing process demands a lot more work when laying the flooring, and joints of this kind are often not sufficiently long-lasting.
In practice, there is therefore a preference for the type of edge profiles that guarantee an interlocking connection between adjacent tiles in the horizontal direction as well as the vertical.
Interlocking joints of this type are disclosed in the above-mentioned publication as well as in GB 2 256 023 A, WO 98/58142, U.S. Pat. No. 4,426,820, DE-OS 2 238 660, DE 79 28 703 U1 and DE 198 54 475 A1.
In the process of laying the floor tiles described here, the edge profile of each consecutive tile is generally held at an angle and pushed or slotted into the edge profile of a tile that has already been laid, and then lowered into a horizontal position. This ensures that both edge profiles lock into each other. A floor surface that has been laid in this way is removed by executing the steps in reverse order. This type of assembly or disassembly method is only possible, however, if there is sufficient space above the flooring for the tiles to be positioned at an angle. This is not always the case, e.g. under heating elements, pipes, chimney, seats and other fixed installations.
This invention is therefore based on the task of providing a floor tile of the above-mentioned type with a modified groove and tongue joint as defined above which will lock into place in the horizontal direction as well, but which can be laid not only by angling and lowering consecutive tiles during the assembly process, but also by pushing tiles together horizontally to create a snap-lock effect.
In the case of a floor tile of the type mentioned above, this task is solved in that the groove in the first tile is disposed directly above its tongue, in that the lower wall of this groove falls off towards the back end of the groove by the same amount as the tongue on the first tile rises upwards, in that the upper wall of the groove in the first tile runs essentially parallel to the plane of the tile, and in that the tongue on the second tile matches the shape of the groove in the first tile by having a top surface that runs essentially parallel to the plane of the tile and a bottom surface that falls off towards the end of the tongue.
Whilst an edge joint of this type offers sufficient locking in the horizontal direction against unintentional separation of adjacent tiles, it also has relatively flat, less acutely angled undercuts allowing adjacent tiles to be pushed together or taken apart horizontally, at least when a certain amount of force is applied. Under conditions of normal use, however, the snap effect is sufficient to hold the tiles in position adjacent to each other.
With regard to the terminology used here, it should be noted that comments are always made with reference to the tiles in the position in which they are shown in the drawings, which will be explained below. The terms xe2x80x9ctopxe2x80x9d and xe2x80x9cbottomxe2x80x9d in particular are to be understood in this sense. It is also evident, however, that the arrangement could equally well be reversed, i.e. that the positions xe2x80x9ctopxe2x80x9d and xe2x80x9cbottomxe2x80x9d can be interchanged without leaving the scope of the invention.
Floor tiles of the above-mentioned type are generally made from timber materials, in particular medium or high thickness fibreboard, but also from solid wood. Support tiles made from synthetically produced materials or recycled materials such as e.g. polyurethane recycling materials could also be used. The applicability of this invention is not limited with regard to the type of tile material that is used.
The extent of the undercut resulting from the interaction of the tongue on the first tile and the groove in the second tile will also depend in each case on the elasticity of the material. The undercut can be defined by selecting the inclination and the length of the tongue on the first tile. As a general rule, an angle of 15xc2x0 is appropriate.
To facilitate the joining process, the edges at the front end of the tongues and the edges at the entrance to the grooves should preferably be tapered.
The tongue on the second tile is preferably disposed directly above its groove. The tongue on the second tile therefore forms the top limit of the groove in the second tile. The bottom surface of the tongue on the second tile is therefore inclined by the same degree as the tongue on the first tile. Whilst the tongue on the first tile has two essentially parallel top and bottom surfaces inclined upwards at an angle of e.g. 15xc2x0, the lower surface of the tongue on the second tile is inclined downwards towards the free end, as already mentioned, whilst the upper surface is essentially horizontal, i.e. parallel to the tile plane of the tiles to be joined. It is preferable to ensure that the projecting edges on the top and bottom sides of the tongue on the second tile are also tapered. The bottom edge simultaneously forms the top edge of the groove in the second tile.
In the event that the locking effect of the above-mentioned edge joint is insufficient, provision can be made for an additional locking rib which engages with a locking groove in the other tile. The locking rib can be disposed either on the top or bottom surface of one of the tongues, or, alternatively, on the top or bottom wall of one of the grooves. The locking rib is preferably disposed on the top surface of the tongue on the second tile and the matching locking groove is disposed in the top wall of the groove in the first tile. Basically, however, it is of no importance on which of the tongues the locking rib or locking groove takes effect, or whether this happens on the top or bottom side of the tongue.
If this additional locking means is used, the two tongues could be made shorter, or could be angled to a lesser degree.
The vertical cross-section of the locking rib and locking groove is preferably contrived as a trapezoidal or rounded trapezoidal shape which therefore has sides that slope to a greater or lesser degree. Steep or even vertical sides result in greater rigidity, but render the assembly or disassembly process more difficult.
Other features and advantages of the invention derive from the sub-claims. Preferred embodiments of the invention will be explained in more detail below with reference to the enclosed drawings, in which: